I did 200mg diphenhydramine followed by 150mg of dxm the other day to see how they would work together. I think I should have done them in reverse order beacuse the benedryl made me way to tired and I kept going into those little benedryl vision things where u close your eyes and sorta have a dream while your awake and then u open you eyes and realise you are still in your room. I finally felt the dxm kick in but 150mg wasnt really enough to do shit and I just got that light dxm body feel added to my already super heavy/tired benndry state. I then went to bed cuz I was so tired. It wasnt really a good or bad expierence, not very exciting and had a very dreamy feel due to the diphenhydramine. Woke up the next morning feeling fine. cheers.